The critical micelle concentration (CMC) values of a 49-surfactant dataset, among them 30 derived from α-hydroxy acids or from gluconolactone synthesized and characterized in our laboratory, were subjected to Quantitative Structure Property Relationship (QSPR) studies. In this study, a principal component analysis (PCA) was used to compare the behavior of the synthesized surfactants to commercial ones that are used as detergents. The PCA shows the importance of the molecular structure of a surfactant in determining its activity (application field). We found that gluconolactone derivatives exhibited the same activity as those observed for glucopyranoside derivatives. A partial least squares regression was used to build a model that describes the CMC of diverse surfactants as a function of molecular descriptors.Paper no. S1264 in JSD 5, 45-53 (January 2002).The Quantitative Structure Property Relationships (QSPR) philosophy assumes that the behavior of a compound, as expressed by any measured property, can be correlated to a set of molecular features of the compound. QSPR are constructed from experimental property data and a series of descriptors-terms representing the chemical characteristics of the system. Typical descriptors include thermodynamic properties or functions representing molecular shape. By computing and analyzing QSPR, some factors can be identified that are critical to the properties assigning the design. The critical micelle concentration (CMC) is an extremely useful value, as it captures the surface and interfacial activity of the surfactants in solution. The ability of surfactants to reduce surface or interfacial tension is expected to be related to the CMC. A low CMC indicates that it is thermodynamically favorable for the hydrophobic domain of the surfactant molecule to leave the aqueous solution. It is well known that CMC depends on molecular structure. Several attempts have been made to obtain a quantitative structure property relationship for prediction of the CMC. A linear relationship has been found between the logarithm of the CMC and the number of alkane carbon atoms for homologous series (1),where A and B are empirical regression coefficients. Ravey et al. (2) found similar relationships between the CMC and the number of ethylene oxide residues. Becher (3) described a very good relationship for linear alkylethoxylate surfactants between log (CMC) and the carbon number, n, on one hand and the ethylene oxide number, m, on the other hand. Ravey et al. (2) improved the correlation by including a nonlinear term in the form of the product of the alkane carbon number and the ethylene oxide number, n × m, log (CMC) = A + Bn + Cm + Dnm [2]However, some QSPR studies (4-6) have been carried out on the physicochemical phenomena. Stanton and Jurs (4) used the partial charged surface area descriptor to correlate surface tension of organic molecules. Employing partial charged surface area descriptors, they developed a sixparameter model (R 2 = 0.908, F = 39) for a set of 31 organic molecules. Katrizk...

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